package com.study.utils;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {

    private static final long BEGIN_TIMESTAMP = 1640995200L;

    private static final int COUNT_BIT = 32;

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    public long nextId(String keyPrefix) {
        //生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long time = nowSecond - BEGIN_TIMESTAMP;

        //生成序列号
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        Long count = stringRedisTemplate.opsForValue().increment("incr:" + keyPrefix + ":" + date);
        return time << COUNT_BIT | count;
    }
}
